1. Field of the Invention
This invention relates to a novel polysiloxane water absorbing contact lens. These contact lenses are water absorbing, soft, hydrophilic, flexible, hydrolytically stable and biologically inert. The contact lens are prepared from the polymerization of hydrophilic sidechains containing polysiloxane monomers. The polysiloxane monomers are .alpha.,.omega. terminally bonded through divalent hydrocarbon groups to polymerizably activated unsaturated groups. These monomers are polymerized to form polymers in a crosslinked network. The polymers and/or copolymers are preferably optically clear and colorless. The polymers and copolymers described herein may be employed for making "hard" or "soft" contact lenses, intraocular implants, as well as other prostheses, more particularly "soft" contact lenses which are water absorbing and hydrophilic.
2. Prior Art Statement
U.S. Pat. No. 4,153,641 teaches contact lenses made from polymers and copolymers comprising poly(organosiloxane) polymers and copolymers formed by polymerizing a poly(organosiloxane) monomer .alpha.,.omega. terminally bonded through divalent hydrocarbon groups to polymerized, free radical polymerizably activated, unsaturated groups forming a polymer in a cross-linked network. Additionally, specific comonomers are disclosed which include lower esters of acrylic and methyacrylic acid, styryls and N-vinyl pyrrolidinone which may be copolymerized with the above described poly(organosiloxane) monomer to form a copolymer. The preferred polysiloxane monomers of the instant invention include the same poly(organosiloxane) monomers described above, with the important exception, that the instant polysiloxane monomers additionally contain hydrophilic sidechains. These sidechains result in the polymer formed, being not only hydrophilic, but most importantly water absorbing. Therefore, it was unexpectedly discovered that when the instant polysiloxane monomers, described above, contained hydrophilic sidechains and were polymerized, a water absorbing polysiloxane polymer was formed. This polymer was extremely suitable for making hydrophilic, water absorbing, soft contact lenses. It is generally known in the siloxane art that siloxanes are hydrohobic. There are a few instances where the art teaches hydrophilic polysiloxanes. We know of only one instance, in the prior art, where a polysiloxane is disclosed as being capable of absorbing water. However, this known material as disclosed in U.S. Pat. No. 4,136,250 would not be suitable for making the instant contact lens for the reasons stated herein concerning U.S. Pat. No. 4,136,250 as prior art.
U.S. Pat. No. 4,136,250 teaches in pertinent part, a water absorbing polysiloxane which may be used to make soft contact lenses which is obtained by copolymerizing the following siloxane monomer: ##STR1## in which R.sub.1 can be ##STR2## with a variety of hydrophilic monomers including acrylic acid. The above siloxane monomers can be reduced to a formula similar to but yet critically different from the instant hydrophilic sidechain containing polyorganosiloxane monomers. From the pertinent teachings of U.S. Pat. No. 4,136,250 the following siloxane monomer may be derived: ##STR3##
The oxygen atom in the monomer backbone, with the arrow pointing to it, is present in the '250 formula but not present in the instant hydrophilic sidechain containing polyorganosiloxane monomers. This oxygen atom presents several problems. This particular oxygen atom, because of its placement between the silicone and carbon atoms, is subject to hydrolysis and alcoholysis. This bond will hydrolyze, even at room temperature, in the presence of water. Stability is important, if this material is to be used for biomedical devices, such as, contact lenses, since these types of devices are usually heated in water in order to disinfect them. If, during disinfecting the contact lens loses its shape, then it loses its optics. This means that the material taught in '250 would be undesirable for use in certain medical devices including contact lenses. The instant hydrophilic sidechain containing polyorganosiloxane monomers results in polymers and copolymers which have superior hydrolytic stability since there is no Si--O--C linkage.
Also to be considered are the examples of '250. Only in these examples of '250 are there specific monomers disclosed without this undesirable Si--O--C linkage. However, these specific monomers have undesirable urethane linkages or couplings which present structures which are even more different from the instant monomers. The urethane linkage, i.e., ##STR4## as mentioned, is also undesirable for use in medical devices, particularly contact lenses. However, in addition, the instant hydrophilic sidechain containing polyorganosiloxane monomers have no urethane linkages.
U.S. Pat. No. 4,138,382 teaches, in pertinent part, a hydrophilic, water swellable, crosslinked copolymer gel. This copolymer gel is a hydrogel, such as N-vinylpyrrolidone crosslinked with a low molecular weight siloxane. The siloxane component is a very small constituent and is present for the purpose of crosslinking. The siloxane is not present in amounts more than about 2 percent by weight. This does not teach a hydrophilic, water absorbing siloxane, much less a contact lens made therefrom.
Dutch Pat. No. 7,704,136 published Oct. 18, 1977 teaches, in pertinent part, a wettable siloxane material for use in making contact lenses. However, '136 teaches that the wettable contact lenses should not absorb water since water absorption, as taught in '136, would cause water to be discharged into the eye when the contact lenses are in use. This is viewed as a disadvantage in '136. The instant invention concerns a hydrophilic sidechain containing polysiloxane contact lens which absorbs water in larger amounts. Water absorption is viewed by the instant inventors as an advantage. The Dutch reference '136 further teaches that a lens should not absorb water since, as taught in '136, such a lens would undergo changes, such as, changing its optical properties. '136 further teaches that the handling of such a lens is difficult because, when it is swellable, it is physically weak. However, the instant lenses are made from hydrophilic sidechain containing polysiloxane material which is strong, durable, water absorbing and oxygen permeable. The Dutch patent further refers to some of the monomers which may be reacted with the polysiloxanes taught in '136 which are esters of glycidyl alcohol and esters of certain acids including acrylic acid and methacrylic acid. '136 also suggest the use of specific anhydrides such as maleic anhydride. Nowhere does this Dutch reference '136 disclose the instant hydrophilic sidechain containing polysiloxanes or that certain comonomers may be reacted with these monomeric hydrophilic sidechain containing siloxanes in order to form the instant water absorbing polymers or copolymers as disclosed herein.
U.S. Pat. No. 3,808,178 discloses, in pertinent part, a polymeric material containing a polymethacrylate backbone with relatively short poly(organosiloxane) ester sidechains on the backbone polymer. There is no crosslinking involved in '178 since the monomers disclosed in '178 are monofunctional, i.e., have only one functional group on each monomer. In order to get crosslinking in '178 it is taught at column 5 of '178 that different monomers must be added for crosslinking which have more than one functionality. However, in the instant invention crosslinking is obtained since each hydrophilic sidechain containing siloxane monomer is difunctional, i.e., each hydrophilic sidechain containing siloxane monomer contains two .alpha.,.omega. functional groups, most preferably two methacrylate groups which results in crosslinking. Not only does '178 not teach the hydrophilic sidechain containing polysiloxane monomers used in the instant invention but '178 does not remotely teach making the instant hydrophilic siloxanes which are also water absorbing into soft, hydrophilic, water absorbing contact lens.
W. A. Piccoli, G. G. Haberland and R. L. Merker, J. Am. Chem. Soc., "Highly Strained Cyclic Paraffin-Siloxanes", vol. 82, pp. 1883-1885 (Apr. 20, 1960) teaches, in pertinent part, the preparation of the cyclic paraffin-siloxane monomers which may be used in the instant invention to make the instant preferred siloxane prepolymers but not siloxane prepolymers which contain hydrophilic sidechains. These preferred hydrophilic sidechain containing siloxane prepolymers, i.e., linear monomers, in the instant invention are then polymerized and crosslinked to form the preferred polymers used for making contact lenses. It is disclosed on pg. 1884, col. 2, lines 15-27, of the above article that these cyclic paraffin-siloxane monomers may be polymerized using strong acids or bases to form linear polymers. The preferred hydrophilic sidechain containing siloxane linear polymers, as mentioned, are used in the instant invention as preferred prepolymers are polymerized and crosslinked to form materials for making contact lenses. Nowhere does the article disclose or suggest the crosslinked water absorbing hydrophilic sidechain containing polysiloxane polymers of the instant invention.
U.S. Pat. No. 2,770,633 discloses 1,3-bis(4-methacryloxybutyl) tetramethyl disiloxane, one of the preferred siloxane monomers, without the instant hydrophilic sidechains, used in the instant invention. This is taught at col. 1, line 63 of '663 when R equals vinyl. However, '633 teaches only the siloxane monomer whereas the instant invention teaches not only the siloxane monomers but the hydrophilic sidechains must be attached to these monomers and then polymerized or copolymerized in order to form a hydrophilic, water absorbing hydrophilic sidechain containing polysiloxane material for use in making soft contact lenses. '633 would not want the monomer disclosed in '633 to polymerize since it would not perform its intended function as a lubricant, if polymerized.
U.S. Pat. No. 2,906,735 teaches a reaction between an alkyl siloxane and acrylic acid or a methacrylic acid resulting in a disiloxane terminated by acrylate groups. '735 does not teach the water absorbing hydrophilic sidechain containing polymers of the instant invention.
U.S. Pat. No. 2,922,807 discloses disiloxanes having acryloxy or methacryloxy groups attached to the silicone through a divalent alkylene radical of from 2 to 4 carbon atoms. '807 does not teach the water absorbing hydrophilic sidechain containing polymers of the instant invention, much less, contact lens made therefrom.
U.S. Pat. No. 3,763,081 dicloses, in pertinent part, the polymerization of an unsaturated siloxane, which is somewhat difficult to polymerize, since a double bond in this type of monomer generally is not very active. One must use both high temperatures and a peroxide catalyst or a platinum catalyst in order to complete this type of reaction. See, for example, '081 at col. 4, lines 35-46. In the instant preferred reaction the monomeric material is referred to specifically as having activated unsaturated groups bonded through a divalent hydrocarbon group to the siloxane whereas '081 has no activated unsaturated groups bonded to the siloxane. Furthermore, '081 does not teach the water absorbing hydrophilic sidechain containing polymers of the instant invention, much less, contact lens made therefrom.
U.S. Pat. No. 2,865,885, in pertinent part, teaches a vinyl group which is not activated as shown in col. 1, lines 25-30 of '885. The reason '885's double bond is not "active" in the sense as defined in the instant application is that the double bond is bonded to either sulfur or oxygen. In the instant invention this same position would have a ##STR5## carbonyl group. This would make the double bond active as defined in the instant application. In the instant invention the vinyl groups are "activated" to facilitate free radical polymerization. The formula given at col. 1, lines 25-30 of '885 does not lend itself to free radical polymerizatin due to the lack of resonance but rather it lends itself to ionic polymerization due to the polar nature of the substituents. Therefore, it would be extremely difficult, if at all possible, for '885 to form the compounds of the instant invention. Also, the compounds formed in '885 are not hydro-lytically stable because of the presence of the silicone-nitrogen bond in the formula. The instant invention cannot use a hydrolytically unstable compound. Furthermore, the products of this hydrolysis in '885 could be injurious to the human eye particularly the amines. Also, at col. 3 of '885 the linkage is an amine linkage to the double bond and in the instant invention this linkage is never an amine linkage. Therefore, '885 does not teach the instant hydrophilic sidechain siloxane containing monomers much less the instant water absorbing polymers.
U.S. Pat. No. 2,793,223 teaches, in pertinent part, at Example 5 at col. 3, lines 30-41 that a phenyl group is attached to the siloxane. Therefore, that material would be very hard. Contact lenses made from the polymers made from the monomers disclosed in '223, because of the presence of the phenyl group on the siloxane as shown in Example 5 of '223, would not transport oxygen sufficiently whereas contact lenses made from the instant polymers would transport oxygen sufficiently to meet the oxygen requirements of the human cornea. Furthermore, neither are hydrophilic sidechains disclosed in '223.
U.S. Pat. No. 3,228,741 teaches, in pertinent part, a silicone contact lens in general. However, nowhere are any hydrophilic sidechains disclosed. Neither does '741 teach a hydrophilic, water absorbing siloxane contact lens as in the instant invention.
U.S. Pat. No. 3,700,573 teaches, in pertinent part, radiation grafting of hydrophilic polymers to polysiloxanes. These siloxanes are then used in making contact lens. One skilled in the art would be taught that something must be done to polysiloxanes in order to make them hydrophilic. As taught in '573, silicones are inherently hydrophobic. In '573 the surface is treated in order to make this material hydrophilic. Surface treatment is not as effective as the instant invention for making a siloxane hydrophilic. Surface treatment only affects the surface on the contact lens. This surface can be removed, for example, by abrasion. However, in the instant invention, the siloxane material is hyrophilic throughout. Also, and most importantly, the instant material is water absorbing.
U.S. Pat. No. 3,916,033 teaches, in pertinent part, radiation grafting hydrophilic polymers onto polymethyl siloxane in order to make it hyprohilic. This material is then used to make contact lens. More specifically, '033 teaches using polydimethylsiloxane and radiation grafting onto the surface of this material, N-vinyl-pyrrolidone. As mentioned, grafting is not used in the instant invention.
U.S. Pat. No. 3,458,553 teaches, in pertinent part, a paraffinsiloxane which is not used in the instant invention but this siloxane contains either an amide or a cyano sidechain.
U.S. Pat. No. Re. 25,727 teaches, in pertinent part, an ether sidechain siloxane which is made by hydrosilation. The ether sidechain silicone is used as a surfactant. The siloxane is endcapped with trimethylsilyl groups. This siloxane backbone material is not used in the instant invention. Furthermore, '727 does not polymerize the material to form shaped bodies since the material disclosed in '727 is used as a surfactant. One does not polymerize a surfactant to a solid material if used as a surfactant.
U.S. Pat. No. 2,723,987 teaches, in pertinent part, a carboxylate, i.e., a carboxylic acid sidechain siloxane. The carboxylic sidechains are reacted with either an alcohol or an amine to make a polyamide or polyester. This is an intermediate material. These intermediates are particularly useful in the preparation of siloxane modified alkyd resins. '987 does not teach that the material, i.e., either the ester sidechain siloxanes or the carboxylic acid sidechain siloxanes by themselves can be cured to form shaped bodies. Also, in '987 the curing is done through the carboxylate groups by combining this with the polyalcohol or polyamine. This is not done in the instant invention. Neither are the backbones disclosed in '987 utilized in the instant invention.
U.S. Pat. No. 2,762,823, in pertinent part, teaches an amino sidechain siloxane. '823 describes the preparation of amino sidechain siloxanes. These amino sidechain siloxanes are not cured to form shaped bodies. Also, the amino functionality is used to react with polyacids to form polyamide type resins. These materials disclosed in '823 are cured through the amine groups by reacting with a diacid chloride, etc. This type of reaction is not used in the instant invention. In '823 the sidechain siloxanes are intermediates to form further end product. Furthermore, neither are the instant siloxane backbones disclosed in '823.
U.S. Pat. No. 2,770,631 teaches, in pertinent part, hydroxy ester substituted siloxanes. '631 teaches that a carboxyl group can be attached to the siloxane via a CH.sub.2 radical. '631 does not teach any sidechains longer than a CH.sub.2. However, the instant invention utilizes some of these sidechains materials and the longer chains would be more hydrolitically stable. It is known that hydroxy groups and ester groups that are alpha to silicone are much more stable than the beta substituted siloxanes. Also '631 does teach an ester that has an hydroxy group in the sidechains. However, the instant siloxane backbones are not taught in '631. Furthermore, the compounds are used in '631 as lubricants, sunscreen agents and these materials are soluble in silicone fluids which make them valuable as antioxidants and stabilizers for greases, etc. However, nowhere does '631 teach that the hydroxy ester sidechain siloxanes are cured to form a shaped body much less hydrophilic, water absorbing siloxane contact lenses. '631 would not want a polymerized material since these materials are used in lubricants and should remain fluid.
However, as mentioned, '631 does prepare an hydroxy ester sidechain siloxane, a vinyl sidechain siloxane, a phenyl sidehchain siloxane but, as mentioned, does not cure them into shaped bodies or use the instant siloxane backbones.
U.S. Pat. No. 2,770,632 teaches, in pertinent part, an ester acid sidechain siloxane. The only length of the alkyl attaching the ester to the silicone is a CH.sub.2 group. '632 does not teach longer chains. However, these short sidechains are used in the instant invention. Most importantly, however, these materials are used as lubricants and emulsifying agents, etc. Also, '632 makes the metal salts of the carboxylic acid which are utilized as sidechains in the instant invention but '632 uses these simply as emulsifying agents. In '632, these materials should not be polymerized due to the end uses taught in '632. However, these materials in '632 can be cured using polyhydric alcohols but these cures are not utilized in the instant invention. Most importantly, the backbones of the instant siloxanes are not disclosed in '632.
U.S. Pat. No. 2,819,245 teaches, in pertinent part, hydroxy sidechain siloxanes, amino sidechain siloxanes, carboxylic acid sidechain siloxanes, amide amino sidechain siloxanes, amide amino carboxylate sidechain siloxanes, all of which are utilized in the instant invention. However, '245 does not teach that these materials can be cured since these materials are used to react with epoxides. '245 uses the functionality present to react with an epoxy resin which is then cured. The instant invention does not do this. Furthermore, '245 does not teach contact lens or shaped bodies and most importantly does not teach the siloxane backbones of the instant invention.
U.S. Pat. No. 2,823,195 teaches, in pertinent part, reacting a carboxylic acid sidechain siloxane with a diamine to form a polyamide. The siloxane is being used as an intermediate. The siloxane, as mentioned, is reacted with a diamino or a triamino compound to make a polyamide. This reaction is not used in the instant invention. Neither does '197 teach a shaped body much less a water absorbing contact lens or even a contact lens. Most importantly, '197 does not teach the siloxane backbones of the instant invention.
U.S. Pat. No. 2,838,423 teaches, in pertinent part, an amide sidechain siloxane which is then reacted with formaldehyde and pyridine to make a pyridium salt. In '423 the material is used as s water repellent for fabrics. The salt sidechain siloxane is used in '423 in a relatively low percentage in order to make the siloxane adhere to the fabric. '423 is actually teaching using the polar sidechain as a binding agent for the fabric since '423 is making the fabric hydrophobic rather than hydrophilic. Therefore, '423 is using a salt for hydrophobic purposes. The instant invention is using this sidechain siloxane in order to make the siloxane contact lens hydrophilic and most importantly water absorbing. Also, neither does '423 teach the endcapped siloxane backbone of the instant invention.
U.S. Pat. No. 2,842,517 teaches, in pertinent part, an alcohol sidechain siloxane or a carboxylic acid sidechain siloxane. These may be reacted with an unsaturated diacid to make polyester resins. '517 uses a carboxylic group or the alcohol group as a curing functionality. This reaction is not utilized in the instant invention. Furthermore, '517 does not make shaped bodies with the siloxanes but reacts these siloxanes with other materials in order to make shaped bodies. However, the end product is not the instant endcapped siloxanes nor are the shaped bodies, contact lens.
U.S. Pat. No. 2,855,381 teaches, in pertinent part, amide sidechain siloxanes. '381 cures these siloxanes to form rubbers. '381 incorporates the amide sidechains into the siloxanes to make the silicone rubber more resistant to attack by hydrocarbon solvents and oils. '381 cures these siloxanes with a benzoyl peroxide cure. However, the instant benzoyl peroxide cure is completely different than the cure taught in '381. Therefore, '381 is only teaching how to make the silicone rubbers more resistant to oils. '381 does not teach that this makes the silicone rubber hydrophilic and '381 does not teach that this would make the silicone rubber water absorbing. Neither does '381 teach hydrophilic, water absorbing contact lens nor does '381 teach the endcapped siloxanes of the instant invention.
U.S. Pat. No. 2,894,967 teaches, in pertinent part, carboxylates and alcohol sidechain siloxanes. '967 teaches using these materials as chromium complexing agents. These materials are not used to form shaped bodies. Neither does '967 teach the endcapped siloxanes of the instant invention.
U.S. Pat. No. 2,924,587, U.S. Pat. No. 2,924,588 and U.S. Pat. No. 2,925,402 teach, in pertinent part, either alcohol sidechain siloxanes or carboxyl sidechain siloxanes, both of which are utilized in the instant invention. However, nowhere do these references, including '587, teach hydrophilic, water absorbing contact lenses. In '402, the material is cured with diacids, diisocyanates, diols, diamines, etc. These reactions are not used in the instant application. '588 teaches alcohol sidechain siloxanes. '588 teaches that functional siloxanes can be used to react with polyfunctional organic compounds such as dicarboxylic acids or diisocyanates to give a resinous material. '588 does not teach that one can take these materials per se and cure them into useful shaped bodies. These materials must be reacted with other materials in order to form shaped bodies. That is much different than in the instant application. Furthermore, neither does '587, '588 or '402 remotely teach the instant endcapped siloxanes.
U.S. Pat. No. 3,057,901 teaches, in pertinent part, a polyether alcohol sidechain siloxane. '901 teaches that this siloxane may be used as a surfactant. This patent does not teach the instant endcapped siloxanes, much less contact lens made therefrom.
U.S. Pat. No. 3,215,643, in pertinent part, teaches sulfate salt sidechain siloxanes. '643 teaches using this material for foaming solvents. This patent does not teach the instant endcapped siloxanes nor that these materials may have hydrophilic sidechains and be made into water absorbing contact lens.
U.S. Pat. No. 3,215,718 teaches, in pertinent part, sulfonic acid sidechain siloxanes. These materials are useful as water repellents for textiles. This patent does not teach the instant endcapped siloxanes much less that these materials may have hydrophilic sidechains and be made into water absorbing contact lens.
U.S. Pat. No. 3,246,048 teaches, in pertinent part, a polyether sidechain siloxane. The polyether is endcapped with an hydroxyl group. '048 teaches using the hydroxyl group for curing with a polyurethane. '048 does not teach the instant endcapped siloxanes nor that these materials may be made into water absorbing contact lens.
U.S. Pat. No. 3,249,586 teaches, in pertinent part, siloxane with a cyclic amide sidechain. In '586 this material is prepared by hydrosilation. The siloxane material of '586 can be useful as thermoplastic, elastomeric and resinous material. Nowhere does '586 teach that the final material is hydrophilic or water absorbing or that it can be used to make contact lens. Neither is the instant endcapped siloxanes disclosed or suggested by '586.
U.S. Pat. No. 3,317,460 teaches, in pertinent part, a polyalcohol sidechain siloxane. '460 teaches making copolymers with di- and trifunctional siloxanes. These materials are useful as curing agents for isocyanate prepolymers, for preparing polyurethane rubbers and for making varnishes. '460 does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be made into water absorbing contact lens.
U.S. Pat. No. 3,317,577 teaches, in pertinent part, a polyamino sidechain siloxane. '577 teaches that this material may be used as a surfactant. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing a hydrophilic sidechain, can be made into water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,328,449 teaches, in pertinent part, a sulfonic salt sidechain siloxane. '449 teaches that this material may be used as detergents, ion exchange resins, wetting agents, antistatic agents for synthetic fibers and polymerization catalysts for siloxanes. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing a hydrophilic sidechain, can be made into water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,338,943 teaches, in pertinent part, an amino sidechain and carboxyl sidechain copolymer which is then formed into an internal salt. '943 teaches that this material can be used as a protective coating for metals, etc. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing a hydrophilic sidechain, can be made into water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,355,425 teaches, in pertinent part, a pyridine sidechain siloxane. '425 teaches using these materials for dyeing fabrics. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing a hydrophilic sidechain, can be made into water absoring contact lens as in the instant invention.
U.S. Pat. No. 3,355,455 teaches, in pertinent part, the same sort of composition as in U.S. Pat. No. 3,355,425. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing a hydrophilic sidechain, can be made into water absorbing contact lens as in the instant invention.
U.S. Pat. Nos. 3,398,104 and 3,402,192 teach, in pertinent part, ether sidechain siloxanes. The degree of polymerization of the ether sidechain is from 25 to 100. These materials are used as surfactants in the preparation of polyurethane foams. These patents do not teach the instant endcapped polysiloxanes nor that these materials, when containing a hydrophilic sidechain, can be made into water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,440,261 teaches, in pertinent part, an amino amide sidechain siloxane. This material is used as textile treating agent to improve the dyeability of the textile, and as creaseproofing and water repellent agents for textiles. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,508,959 teaches, in pertinent part, a siloxane which contains a sidechain which has sulfur, oxygen, ester, amide, amine, sulfonates, sulfonomide and multi-amino sidechains that are attached to the silicone. These materials are being used to render surfaces anticoagulative. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,512,915 teaches, in pertinent part, a diamino sidechain siloxane used for textile dyeing. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,518,288 teaches, in pertinent part, a polyether sidechain siloxane which is used as a surfactant. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,560,543 teaches, in pertinent part, a polyamino sidechain siloxane. This patent does not teach the instant endcapped polysiloxanes or that these materials when containing a hydrophilic sidechain can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,560,544 teaches, in pertinent part, a trimethylsilyl endcapped siloxane which has a polyether-ester-acid sidechain attached. This patent does not teach the instant endcapped polysiloxanes or that these materials when containing a hydrophilic sidechain can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,627,806 teaches, in pertinent part, a mono or dicarboxylate sidechain silane. This material is used as adhesion promoters for silicon rubber. This patent does not teach the instant endcapped polysiloxanes or that these materials when containing a hydrophilic sidechain can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,703,486 teaches, in pertinent part, a siloxane which contains a sidechain which has a solubilizing group attached. The solubilizing group may be either COOH, carboxylic acid, carboxylic acid ester, amide, amine, cyano, thio, hydrocarbon or a ketone. This material is used as a polymer for foam. In the instant invention, the solubilizing group sidechains act not only as hydrophilic sidechains but these sidechains tend to increase the solubilizing factors. '486 is using solubilizing sidechains but for a completely different reason. '486 is using a completely different type of system than in the instant invention. Also, this patent does not teach the instant endcapped polysiloxanes or that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,729,444 teaches, in pertinent part, a carboxylic acid sidechain siloxane, copolymerized with difunctional siloxanes. This material is used to enhance paper's resistance to wetting. Also, this patent does not teach the instant endcapped polysiloxanes or that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,734,763 and U.S. Pat. No. 3,843,529 teach, in pertinent part, siloxanes which contain quaternary ammonium sidechains. These materials are being used as surfactants and lubricants. These patents do not teach the instant endcapped polysiloxanes or that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,846,329 teaches, in pertinent part, a polyether sidechain siloxane as a foam controller. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 2,971,864 teaches, in pertinent part, a diamino sidechain silane. This material is used in latexes. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,884,860 teaches, in pertinent part, a carboxylic acid and sulfide linkage sidechain siloxanes and copolymers with difunctional siloxanes. These materials are useful as resin intermediates in water reducible coating formulations. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,033,815 teaches, in pertinent part, an amino-cyano, an amino ester or an amino amide sidechain siloxane. These materials are useful as sizes for fibrous glass materials. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 2,823,218 teaches, in pertinent part, hydrosilation which is one of the processes used herein. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 2,928,858 teaches, in pertinent part, an amide carboxylate sidechain siloxane. '858 teaches an amide linkage which has a carboxylic acid and carboxylic acid chloride attached thereto. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 2,929,829 teaches, in pertinent part, an amide sidechain siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 2,989,559 teaches in pertinent part, a ketone sidechain siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water asbsorbing contact lens as in the instant invention.
U.S. Pat. No. 3,032,577 teaches, in pertinent part, an amino sidechain siloxane which has hydroxy alkyl groups attached to the amino group. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,071,561 teaches, in pertinent part, a pyridine sidechain siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,152,161 teaches, in pertinent part, an hydroxyalkyl diamino siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,598,785 teaches an amide endcapped siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials when containing hydrophilic sidechains can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,658,867 teaches, in pertinent part, a quaternary ammonium sidechain siloxane. This patent does not teach contact lenses much less the instant contact lenses. Neither does this patent teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,660,452 teaches, in pertinent part, an amino sulfate salt sidechain siloxane. This patent does not teach contact lenses much less the instant contact lenses. Neither does this patent teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lens as in the instant invention.
U.S. Pat. No. 3,737,336 teaches, in pertinent part, an amino sidechain siloxane. This amino endcapped siloxane is used as a hydrophobic coating. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lens.
U.S. Pat. No. 3,836,559 teaches, in pertinent part, quaternary ammonium sidechain siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lens.
U.S. Pat. No. 3,878,168 teaches, in pertinent part, sidechains that have amide, sulfonamide and urea sidechain siloxanes. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lens.
U.S. Pat. No. 4,018,723 teaches, in pertinent part, morpholino modified polyether sidechain polysiloxane. The morpholine group, which has an oxygen and nitrogen in a 6-membered ring, is used as a fire retardant. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lenses.
U.S. Pat. No. 4,049,674, U.S. Pat. No. 4,049,675 and U.S. Pat. No. 4,049,676 teach, in pertinent part, sulfolanyl siloxanes made by hydrosilation. These materials are used as surfactants and as fire retardants. These patents do not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lenses.
U.S. Pat. No. 3,993,606 teaches, in pertinent part, carboxylate salt of an amino siloxane. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lenses.
U.S. Pat. No. 3,586,699 teaches, in pertinent part, an imido sidechain siloxane. This imido group is a nitrogen which has two carbonyl groups attached to it. In '699, it is taught that a cyclic siloxane compound containing one of these sidechains can be polymerized to form a high molecular weight polymer. This material is cured to form an elastomer. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lenses as in the instant invention.
U.S. Pat. No. 3,700,713 teaches, in pertinent part, an ether amide-amino sidechain siloxane made by hydrosilation. This patent does not teach the instant endcapped polysiloxanes nor that these materials, when containing hydrophilic sidechains, can be used to make water absorbing contact lenses as in the instant invention.